C大调中没有升半音和降半音。

There are no sharps or flats in the key of C major.

《牛津词典》

这支乐曲不好演奏，到处是升半音、降半音。

It's a difficult piece to play, full of sharps and flats.

《牛津词典》

我可以分别降半音符号与双倍降半音符号之间的区别。

I can tell the difference between a flat and a double flat notation.

youdao

What we've written is a whole step, so we've got to indicate that this is just a half step away in that fashion, D to E-flat.

而这里写的是一个全音级,所以我们要在这里标出,从D到降E只有半音级

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